The present invention concerns a solid-bowl centrifuge with a drum for separating a mixture of solids and liquid. There is a weir disk between the interior of the drum and a space for conveying the separated liquid off. The weir disk rotates along with the drum, and the inner diameter of the level of the liquid in the interior of the drum depends on the diameter of the weir disk.
A centrifuge of this type is known from German 3 728 901 C1 for example. Since the device that extracts the separated solids is conventionally designed to prevent liquid from flowing off over it, the separated liquid can leave only by way of the inside diameter of the weir disk, which diameter accordingly dictates the level of the liquid in the interior of the drum. The weir in the known centrifuge comprises two disks of different diameter with a gap between them. The weir disks can be actuated as desired by a hydraulically powered slide, creating two different levels of liquid in the drum. The level of liquid cannot be varied continuously, and the design is relatively complicated.